Attachment for grease plugs



FRANK L. FISHER, 01*" MILWAUKEE, W'ISGONSIN.

ATTAGHMENT FOR- GET-EASE PLUGS.

Application filed Juliet), 1921.

1 0 all whom it may concern. 7

Be it known that I, FRANK L. Frsrnnz, a citizen of the United States, and resident of Milwaukee, in the county of Milwaukee and State ofl Visconsin, have invented certain new and useful Improvements in Attachments for Grease Plugs; and I do hereby declare that the following is a full, clear, and exact description thereof.

My invention relates to a new and improved attachment for grease plugs, such as are used in connection with the lubricating cups on cranks and eccentrics for loco motives and similarmachinery.

Great difficulty has been experienced in retaining the plugs in machinery of this kind, owing to the fact that a strong centrifugal force is developed in the operation of the machine, which has a tendency to cause the plugs to work loose and fly out.

It has been the usual custom to provide the inner end of the plug with one or more fins, having more or less abrupt shoulders, which, when the cup is full of grease, will engage same and the resistance of the grease against the shoulder will have a tendency to prevent the plug from working out. Unless the lubricating devices are carefully watched however, the grease will become used up and will no longer exert an effective resistance against the fin.

The object of my invention is to provide a resilient device which will offer at all times. a resistance against the removal of the plug, and will operate more positively than the most eflicient device now in use.

One form in which my invention may be embodied is illustrated in the accompanying drawing, in which,

Figure 1 is a longitudinal sectional view through the grease cup and bushing, and

Figure 2 is a sectional bottom plan view on the line 22 of Figure 1.

Referring specifically to the drawing, the numeral 1 indicates the cup formed on the crank or eccentric, and having the bushing 2 in threaded engagement therewith. A portion of the bushing is cutaway forming a segmental recess 3 intermediate to the ends of the bushing, and along the chord of this segment is located a flat leaf spring 4, the ends of which are formed smooth, as indicated at 5, to prevent any injury to the threads. The usual plug 6 is threaded into the bushing and this plug is formed at its Specification of Letters Patent.

Serial No. 476,229.

innerend with one or more fins '4", having one side inclined, as shown at 8, and the other side 9 formed more abrupt. I also preferably provide a flattened portion 10 intermediate to the ends of the plug.

lVhen the plug is being inserted, the inclined surface 8 of the fin will force the spring 4 outwardly and permit the plug to be screwed in past the same. If the plug works outwardly during the operation of the machine, the spring l, when the end of the plug passes the same, will straighten out, as shown in Figure 2, and upon further movement of the plug, the shoulder or abrupt edge 9 of the fin will contact therewith, and prevent further accidental outward movement of the plug. When the plug is inserted into the bushing far enough for the fiat surface 10 to come in contact with the spring 4, the spring will straighten out against this surface, and form an effective stop to prevent the plug from accidental movement at this point.

From the foregoing description, it will be seen that I have provided an effective and, what might be called, a positive means for preventing the plug from working out of the bushing. The device will work efficiently at all times, whether or not the cup is filled with grease.

lVhile I have shown one specific form in which the invention may be carried out, it is obvious that various minor changes may be made therein, without departing from the spirit of the invention as claimed. it should also be noted that when the plug is inserted so that the spring is bowed, the ends of the spring will, owing to its tension, be firmly engaged. against the side of the cup, and thus not only hold the plug against movement but will also hold the bushing against movement in the cup.

I claim as my invention:

1. The combination of a grease cup having a bushing in threaded engagement ther with, and a plug for threaded engagement with said bushing internally, said bushing having a segmental recess intermediate its ends, a leaf spring normally disposed along the chord of said recess, and frictionally engageable with the periphery of the plug when the latter is inserted, said plug having a fin formed on its inner end and engageable with said spring upon outward movement of the plug after the spring has 110 been released from engagement with the periphery thereof, to prevent accidental re-' moval of the plug from its bushing.

2. The combination of a grease cup having a bushing in threaded engagement therewith, and a plug for threaded engagement with said bushing internally, said bushing having a segmental recess intermediate its ends, a leaf spring normally disposed along the chord of said recess, and having its ends in frictional engagement with the interior of the cup to prevent accidental movement of the bushing therein, the intermediate portion of the spring being frictionally engageable with the periphery of the plug when the latter is inserted, said plug having a fin formed on its inner end and engageable with said spring upon outward movement of the plug after the spring has been released from engagement with the periphery thereof, to prevent accidental removal of the plug from its bushing.

3. The combination of a grease cup havinga bushing in threaded engagement therewith, and a plug for threaded engagement with said bushing internally, said bushing having a segmental recess intermediate its ends, a leaf spring normally disposed along the chord of said recess and frictionally engageable with the periphery of the plug when the latter is inserted, said plug having a flattened portion in its periphery to allow said spring to straighten when the plug is in a certain position with relation to the bushing and to prevent said plug from. being accidentally moved outwardly from said position.

4-. The combination of a grease cup having a bushing in threaded engagement therewith, and a plug for threaded engagement with said bushing internally, said bushing having a *segmental recess intermediate its ends, a leaf spring normally disposed along the chord of said recess, the plug when inserted being engageable with the spring to bow the same and thus exert a frictional resistance against movement of the bushing and plug.

In testimony that I claim the foregoing I have hereunto set my hand at Milwaukee, in the county of Milwaukee and State of Wisconsin.

FRANK L. FISHER. 

